1. Field of the Invention
The invention generally relates to an apparatus and method for lighting water in a water feature, particularly for lighting water with Light Emitting Diodes (LEDs) at least partially in direct contact with the water.
2. Background of the Invention
Increasingly, the popularity of using water as an integral part of domestic landscaping has moved landscapers to include greater numbers of decorative water features. These features are incorporated in swimming pools, spas, ponds, lakes, and other water features and sources in the typical yard. In addition to domestic landscaping, commercial landowners have also been following the trend toward more decorative water elements through fountains, pools, ponds, lakes and such. In response, companies have developed a myriad of features that span the range of naturally occurring water features, such as faux waterfalls complete with jutting rock outcroppings, to more artistic endeavors, like dancing water spouts and jets.
In addition to the natural beauty associated with these features, by applying the proper lighting the beauty of these water features can be extended to include evening viewing. From underwater lighting in pools to back lighting fountains, landscapers have been striving to continue improving how these features are lit.
In relation to lighting water features, some of the earliest attempts to illuminate such water features were made by reflecting high intensity light from light sources which were generally hidden from view or directed onto the feature. While such illumination effects can be quite cost effective, the available light is not used efficiently and the visual effect that results from the light that is reflected to the eye is minimal. Too much of the light is either transmitted past the jets or through the jets. In addition since the light sources must be located in or around or closely adjacent to the water features, it is often the case that, from particular positions around the feature, an observer would be overcome by the intensity of the lights around the feature. This of course would impair the view of the feature and the overall aesthetic.
Several other attempts have been made in the past whereby high intensity light is caused to pass into a chamber from which it passes directly into the stream of the water feature. Using conventional high intensity bulbs in a water tight chamber the light is projected from the chamber towards an outlet or series of lenses leading to an outlet. These attempts include conventional, high intensity pool lighting which uses a watertight compartment to contain a high intensity bulb and passes the light through a lens, such as that seen in U.S. Pat. No. 6,203,173 to Duff et al. In these instances however the light source is located outside the fluid stream and light must be shone into a housing and then passed out into the water. These transmission box arrangements are clumsy and bulky and there is considerable light loss due to transmission losses. These losses occur as the light enters the water tight chamber and on through the lens to the outlet due to dispersion, reflection, and refraction.
Similarly, attempts have been made to include the light enclosures directly in the water channel or pool, effectively moving from a transmission box to a watertight enclosure to contain the high intensity lamp in the water. Such devices are shown in U.S. Pat. No. 4,749,126 to Kessener, et al. and U.S. Pat. No. 6,447,137 to Long. However, these devices simply extended the watertight chamber concept further into the path of the water. While this increases luminosity due to the increased surface area of the enclosure, significant transmission losses still occur due to the space in the watertight enclosure placed around the high intensity lamp. In addition, the location of the lighting system inside the water feature makes the necessary and frequent replacement of bulbs in such systems difficult and costly to manage.
Several innovations using fiber optic lighting systems have been utilized to achieve eye-catching coloration of water features. For instance, U.S. Pat. No. 6,595,675 to Dongo, U.S. Pat. No. 6,375,342 to Koren et al, U.S. Pat. Nos. 6,393,192 and 6,484,952 to Koren, and U.S. Pat. No. 6,132,056 to Ruthenberg show various features with fiber optic lighting systems. However, these fiber optically lit features suffer significantly from the lower luminescence of the transmitted light from the light pump to the tips of the fiber optics, as there are transmission losses and the tips act only as point light sources. In addition to the luminosity problems, the fiber optic lighting systems are costly and significantly more difficult to install and maintain than conventional lights. The fiber optic fibers are very delicate, susceptible to damage even from a slight impact, which makes proper installation difficult. To compound this problem, repair of the individual fibers is extremely difficult and costly. Similar problems exist with maintenance of such features.
To date no feature has been able to achieve the desired superior luminescence and coloring while maintaining durability, increasing dependability, increasing ease of maintenance, and remaining cost effective. There exists a need to provide safe and cost effective water feature lighting with a greater luminescence within the water feature. There should also be a greater ability to control and color the water features, including the ability to color wash and transition between colors within a feature.